The following invention relates to a system and method for recycling and, in particular, a system and method for recycling materials used in a manufacturing process.
Generally, raw materials costs comprise a substantial portion of the cost of manufacturing a particular product. For example, a substantial cost in the production of semiconductors is the cost of the chemicals used during the manufacturing process. Certain chemicals, such as photoresist, comprise a large percentage of this chemical cost and any significant change in the cost of these chemicals will have an impact on the overall cost of the manufactured product.
Many of the chemicals used for semiconductor production are not completely exhausted during the manufacturing process. In fact, the waste stream generated during manufacturing includes a sizeable portion of chemicals such as photoresist and developer. Prior art techniques exist for processing such waste streams to retrieve reusable chemicals contained therein. For example, U.S. Pat. No. 5,084,483 issued to Yamashita is directed to a method for recovering and reusing resist composition scatters in silicon wafer coating. The recovery of the chemicals from the waste stream and their reuse would have a material impact on manufacturing costs.
Although techniques exist for recovering and reusing chemicals from the waste streams of semiconductor manufacturing, these techniques are rarely used and thus have minimal impact on the cost of chemicals used in the manufacturing process. The semiconductor manufacturers themselves have little incentive to reprocess their waste streams because they lack the expertise to do so and such efforts would be a distraction to their main business. Furthermore, the cost to implement a recovery/reuse facility may not be economically feasible if such a facility is to be used to reprocess just the manufacturers own waste streams. The chemical manufacturers also have little interest in promoting chemical recycling as this would reduce their profit margin on new chemicals. Thus, the chemicals contained in waste streams are not recovered and, as a result, the potential costs saving from their reuse is lost.
Accordingly, it is desirable to provide a system and method for recycling materials contained in waste streams generated as a by-product to a manufacturing process.